The present invention relates to data retrieval and more particularly to efficient retrieval of related objects in one operation.
An important use of computers is the transfer of information over a network. Currently, the largest computer network in existence is the Internet. The Internet is a worldwide interconnection of computer networks that communicate using a common protocol. Millions of computers, from low end personal computers to high-end super computers are coupled to the Internet.
The Internet grew out of work funded in the 1960s by the U.S. Defense Department""s Advanced Research Projects Agency. For a long time, Internet was used by researchers in universities and national laboratories to share information. As the existence of the Internet became more widely known, many users outside of the academic/research community (e.g., employees of large corporations) started to use Internet to carry electronic mail.
In 1989, a new type of information system known as the World-Wide-Web (xe2x80x9cthe Webxe2x80x9d) was introduced to the Internet. Early development of the Web took place at CERN, the European Particle Physics Laboratory. The Web is a wide-area hypermedia information retrieval system aimed to give wide access to a large universe of documents. At that time, the Web was known to and used by the academic/research community only. There was no easily available tool which allows a technically untrained person to access the Web.
In 1993, researchers at the National Center for Supercomputing Applications (NCSA) released a Web browser called xe2x80x9cMosaicxe2x80x9d that implemented a graphical user interface (GUI). Mosaic""s graphical user interface was simple to learn yet powerful. The Mosaic browser allows a user to retrieve documents from the World-Wide-Web using simple point-and-click commands. Because the user does not have to be technically trained and the browser is pleasant to use, it has the potential of opening up the Internet to the masses.
The architecture of the Web follows a conventional client-server model. The terms xe2x80x9cclientxe2x80x9d and xe2x80x9cserverxe2x80x9d are used to refer to a computer""s general role as a requester of data (the client) or provider of data (the server). Under the Web environment, Web browsers reside in clients and Web documents reside in servers. Web clients and Web servers communicate using a protocol called xe2x80x9cHyperText Transfer Protocolxe2x80x9d (HTTP). A browser opens a connection to a server and initiates a request for a document. The server delivers the requested document, typically in the form of a text document coded in a standard Hypertext Markup Language (HTML) format, and when the connection is closed in the above interaction, the server serves a passive role, i.e., it accepts commands from the client and cannot request the client to perform any action.
The communication model under the conventional Web environment provides a very limited level of interaction between clients and servers. In many systems, increasing the level of interaction between components in the systems often makes the systems more robust, but increasing the interaction increases the complexity of the interaction and typically slows the rate of the interaction. Thus, the conventional Web environment provides less complex, faster interactions because of the Web""s level of interaction between clients and servers.
A system, method, and article of manufacture are provided for retrieving multiple business objects across a network in one access operation. A business object and a plurality of remaining objects are provided on a persistent store. Upon receiving a request for the business object, it is established which of the remaining objects are related to the business object. The related objects and the business object are retrieved from the persistent store in one operation and it is determined how the retrieved related objects relate to the business object and each other. A graph of relationships of the business and related objects is instantiated in memory.
In an aspect of the present invention, an object navigation pattern of accessing the business object and then accessing relationships with the related objects may be used to retrieve the related objects. In another aspect of the present invention, the relationships between the business and related objects for instantiating the graph of relationships may be determined from a source object, a set of target objects, and the name of the relationship. In one aspect of the present invention, the establishment of which of the remaining objects are related to the business object and the determination of how the retrieved related objects relate to the business object and each other may be pre-processed before retrieving the selected related objects and the business object from the persistent store.
In an embodiment of the present invention, a portion of the objects may also be retrieved from a cache. Also, in another embodiment of the present invention, a batch request may be sent to the persistent store for retrieving the remainder of the objects.